I am using different computers, with Windows XP, Vista and Windows Seven.
On all computers, I set up one user accopunt wirh administrative rights, and one with standard rights (for daily work).
On XP, Rainlendar works without problems for both accounts.
On Vista and Seven, it does not work in the standard accounts.
I already tried to give full access permission to the "Programs" folder, but it did not help.
Right after installing, it did work for one single logon cycle. After rebooting the machines, it did not work on both machines.

Is there any workaround to use Rainlendar in standard accounts for Windows Vista and Windows Seven ?

I'm not able to reproduce this. I created a standard account for Windows 7 and Rainlendar started just fine on it. Can you send me (rainy@iki.fi) the Rainlendar's debug log for the crash (and any other information you find about the crash ...I'm not really sure though where Windows 7 stores the crash info).

at the moment, I don't have access to the Windows 7 computer. But I can reproduce the problem on my Vista machine, too. But it does not happen right after installing, it takes some reboot cycles. And I actived the feature "auto start with windows startup". How can I add the "--debug" statement in combination with the autostart feature ?

Are you able to reproduce this only on the reboot? So if you start the application manually it never crashes? If it crashes only on the boot the Rainlendar's log probably won't be very useful. Does the Vista's "Problem Reports and Solutions" contain anything about the crash?

After installation, I changed the properties of the ".rainlendar2" Folder and all subfolders in my user home directory ("C:\Users\Christian\.rainlendar2") to "invisible".
Because I just don't want to see it at that location.

As long as the folder is invisible, Rainlendar crashes at startup: the tray icon is shown, but not the desktop application. Moving the mouse pointer over the tray icon, makes it disappear.

Switching the folder ".rainlendar2" back to visible, makes everything work fine again.

So, my question is: is it possible to make Rainlendar running even if the user account folders are switched to invisible ?
Or better, move the folder to the following location:
C:\Users\<account>\AppData\Local\
(where other applications like Opera, Firefox, Thunderbird, iTunes etc. store their user specific data)

I also could send two logfiles, one for each case visible/invisible. Their contents are slightly different, burt the logged error messages seem to be identical in both cases.